Editorial: Emerging swine infectious diseases

Surveillance and prevention of infection in clinical xenotransplantation

SUMMARYXenotransplantation, the transplantation of living organs, tissues, or cells between species, carries the potential to address the global shortage of human organs for patients with end-stage organ failure. Recent advances in genetic engineering have improved prospects for clinical xenotransplantation by reducing immune and inflammatory responses to grafts, controlling coagulation on endothelial surfaces, and modifying viral risks, including the porcine endogenous retrovirus (PERV). Management of infectious risks posed by clinical xenotransplantation requires meticulous attention to the biosecure breeding and microbiological surveillance of source animals and recipients and consideration of novel infection control requirements. Infectious risks in xenotransplantation stem from both known human pathogens in immunosuppressed transplant recipients and from porcine organisms for which the clinical manifestations, microbial assays, and therapies are generally limited. Both known and unknown zoonoses may be transmitted from pigs to humans. Some pig-specific pathogens do not infect human cells but have systemic manifestations when active within the xenograft, including porcine cytomegalovirus/porcine roseolovirus (PCMV/PRV), which contributes to graft rejection and consumptive coagulopathy. The role of porcine endogenous retrovirus (PERV) in humans remains uncertain despite the absence of documented transmissions and the availability of swine with inactivated genomic PERV. New technologies, such as metagenomic sequencing and multi-omics approaches, will be essential for detection of novel infections and for understanding interactions between the xenograft, the host's immune system, and potential pathogens. These approaches will allow development of infection control protocols, pathogen surveillance requirements, and tailored antimicrobial therapies to enhance the safety and success of clinical xenotransplantation.

Re-emergence of severe acute diarrhea syndrome coronavirus (SADS-CoV) in Henan, central China, 2023

Severe acute diarrhea syndrome coronavirus (SADS-CoV) was first detected in Guangdong province of China in 2017. And yet from May 2021 to Jun 2023, there were no SADS-CoV outbreaks. In this study, we reported the recent outbreak of SADS-CoV in China on Jun 2023. Phylogenetic analysis showed the novel strain was derived from the ongoing transmission and evolution of SADS-CoV in China, rather than a separate cross-species transmission from bats. Also, the novel strain was found to participate in a recombant event as a minor parent and a missing base in the genome was discovered indicating an novel evolutionary pathway. Through virulence assays in piglets, we further determined that novel strain (SADS-CoV/HNNY/2023) was a highly virulent SADS-CoV strain with typical clinical symptoms: acute diarrhea, vomiting, rapid weight loss. Therefore, the re-emergence of SADS-CoV strains should be brought to people's attention.